Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: TG9 Hop Discussion Date Submitted: July 14, 2014 Source: Robert Moskowitz, Verizon Address 1000 Bent Creek Blvd, MechanicsBurg, PA, USA Voice:+1 (248) 968-9809, e-mail: rgm@labs.htt-consult.com Re: KMP TG9 Closing Report for January 2014 Session Abstract: Is TG9 providing Single or Multi Hop KMP. Purpose: Discuss interaction of TG9 with 15.4 link Hops Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. Robert Moskowitz, Verizon

2. San Diego, CA July 14, 2014 KMP TG9 Link Hop Discussion Robert Moskowitz, Verizon

3. Robert Moskowitz, Verizon Premise • 802.15.9 mechanism can only work over a single link • Fragmentation support mechanism is the limitation • Thus it can only directly provide security for a single hop • A KMP MAY be able to communicate other security conditions • E.G. Group keying

4. Robert Moskowitz, Verizon What is a Hop in 802.15.4 • A Hop is • Transmission of a PPDU by one Device • And reception by another Device • A Hop is a feature of the PHY, not the MAC • MPDUs could be sent over multiple PPDUs • Provided there is a MAC fragmentation function

5. Robert Moskowitz, Verizon What is a Hop in 802.15.4 • Prior 802.15.9 discussions have perhaps confused these points • Typically the 802.15.4 join operation is to a coordinator within radio range and thus a single PPDU • After all, the joining device only learns of MAC addresses within radio range • Could a BEACON have the MAC of a distant coordinator and then forward?

6. Robert Moskowitz, Verizon 802.15.9 Functions at the MPDU Level • KMP called to establish a Security Association between this device and another device • Identified by its MAC address • KMPs tend to have some payloads larger than the smallest MPDU • Thus need for fragmentation support • Has to be within radio range for the ACK based fragmentation function to work • That is a single hop

7. Robert Moskowitz, Verizon 802.15.9 Functions at the MPDU Level • Typically destination MAC addressed 'learned' by listening • For example hearing a BEACON • And then transmitting to that device • KMP over broadcast bad idea, but it COULD work • It MIGHT start with a broadcast • “Hello I am here, anyone to talk to?”

8. Robert Moskowitz, Verizon MPDU Forwarding • Many ways for a PAN to forward an MPDU • Radio relays, 802.15.5, Zigbee mesh, 802.15.10 • But no MPDU fragmentation support

9. Robert Moskowitz, Verizon KMP support between remote devices • 802.15.4 security definitely supports security between remote devices • E.G. a Thermometer and a Thermostat • KMP between these devices requires multi-hop fragmentation support • Higher layer KMP transport required • E.G. HIP, IKEv2, or PANA over IP

10. Robert Moskowitz, Verizon Next step • Prepare text and diagrams • Intro text and diagrams about distinction of PHY links and MAC links